Machine for generating spiral face gears



March 1945. 'E. w, MILLER EIAL MACHINE FOR GENERATING SPIRAL FACE GEARS Filed Jan. 7, 1942 3 Sheets-sheaf 1 i/ 10 F if ii {I ".7.

' /Z 25 V --n'- lllllll uummm I Inveafmu March 1945- w. MILLER ETAL 2,371,702

MAQHINE FOR GENERATING SPIRAL FACE GEARS Filed Jan. 7, 1942 3 Sheets-Sheet 2 Li; I /6 7/ 6M7'14MM' March 20, 1945.

E.. W. MILLER ET AL MACHINE FOR GENERATING SPIRAL FACE GEARS Filed Jan. 7, 1942 I [a 2 a V1 4 s Sheets-Sheet :s

v the type heretofore used;

Patented Mar. 20, 1945 H asrii'zoz a MACHINE For; GENERATING SPIRAL FACE e UNITED STATES, may

GEARS Edward W. Miller and Arthur 1. Bean, Springfield,

Vt., -assignors to The Fellows Gear Shaper Company, Springfield, Vt., a corporation of Ver-- mont- Application January 7, 1942, Serial N0 425,826

' e e Claims The principal object of the present invention is to furnish means for generating face gears of which the teeth are arranged otherwise than at equaldistances from acentralpoint or axis.

One specific type of gear in thecategory referred to has teeth arranged ina spiral of several turns on the plane face of a diskl Such gears heretofore have been made as die castings and the teeth are truncated cones, all alikeas to form and dimensions, spaced equally apart on a spiral pitch line. a U 7 The problem solved with the accomplishment of the foregoing object was to generate in or on ranged in a spiral, or other jnon-circulargpitch spur or helical pinion. In solvingpthis problem we have employed the molding principle of ear generation, using, in certain embodiments of the invention, a rotative and reciprocatory gear shaped planing cutter, and have provided means theface of a disk-like gear element, teetharline which are accurately conjugate toflaf l'ven other form of same result;

r Fig. 8 is a detail 88 offFigfl; e Like reference characters designate the same parts wherever they occur in all the figures. I

' The facegear shownin Fig. 1 is a diskchaw ing on one plane face thereof a series of teeth, I) in spiral arrangement. These teeth are circular in end view and have a tapered profile with their for 'effectingharmonious rotation of the gear ,1

blank andcutterand a relative displacement between the'blank and cutter in accordance, with l the diiferent radial distances of different parts of the tooth bearing zone of such blank from its axis; in combination with means foreffectinga relative reciprocating cutting traverse between thecutter and blank. 4

Mechanical means and mechanisms have been developed in the accomplishment ofthe foregow ing object which, with but slight rearrangements,

largest diameter contiguous to the iace of the disk.- In other words, they are truncated cones. [Gears of this type havebeen madecommercially and incorporated in mechanisms for cooperation withspur pinions. Up-to the present timefno method has been known for making such gears in commercial quantities at tolerable cost except that of die casting.- Whileteeth so fermedand may be used for generating other irregulargears than purely. face gears; that is, external crinternal gears, of either spur'or helical character,

of which different teethare at different distances from the axes, capable of meshing with other gears and pinions in parallel-axis arrangement; some of the possible embodiments of the means above referred to are explained in the following specification with reference tonillustratiye drawings. 7

In the drawings, x e e Fig. 1 is a face view of a spiral face gear' of Fig. 2 is a similar'view of v a face gear made in accordance with the present invention having spirally arranged teeth conjugate to a; spur pin- 1on; V

Fig. 3 is a vertical sectional view, somewhat diagrammatic in" character, of a gear generating machine adapted to make spiral face gears such asthat-shown in Fig. 2; a Fig. 4 is a. fragmentary elevation? showing in face view the cam employed in the machine of constructed certainly" do operate to transmit ro-j, tation to and from meshing pinions, yet they leave 'much to be desired in the way ofi1niformity and smoothness of gear action with the meshing pinions, smoothness of surface finish and long wearing qualities; e e

In accordance with the present invention we have made possible the accurate generation of face gearfteeth in any spiral or other desired non-circular arrangement having faces which are accuratelyconjugatefto the teethof either spur or'helical pinions, as maybe desired, and

which may be made of any metaL metalalloy, or other composition. ormaterialwhich is capable e of being cut by metal cuttingtool's and is other'- wise serviceable for use as a gear element. The

teeth so fashioned have the smoothness of surface fimshcharacteristic of cut gears and the wear resisting qualities characteristic of the metal or other composition from which they are fashioned; Preferably they, are cut in a raised rib protruding from a face of the gear blank, although it is within'our contemplation to make them flush withv the face of the gear by cutting machine for accomplishing the sectional View taken on line are arranged in a spiral of the same outline as that of the gear a in Fig. 1 for convenience of comparison.

All the forms of machine shown in the accompanying drawings as illustrative embodiments of the invention employ a reciprocating and rotating planing cutter having peripheral teeth similar to gear teeth provided with cutting edges at one end; the pitch and pressure angle of such teeth being the same as, those of the pinions or gears with which the face gears to be generated are designed to mesh. Such cutter is designated C in the drawings. It is reciprocated in the direction of its axis, for cutting, and rotated about its axis for generating the prescribed tooth forms in the work. The work piece, or face gear blank, designated W in the drawings of the machine,

is rotated in harmony with the rotation of they cutter and is at the same time displaced with respect to the location in which the cutter performs its reciprocating movements, in equal measure to the different distances of successive teeth from the center or axis of the blank. Means for effecting such a relative displacement between the workand cutter, and means for correlating the rotation of the work with that of the cutter are vitalfactors novel with the .present invention. Their combination with other features, already known in the gear cutting art, are likewise vital novel combinations. A number of possible alternative means for controlling the rotation of work and cutter are shown in these drawings in combination with illustrative means for carrying on the other operations of the machine. 4 1

Referring'now to Figs. 3 and 4, a work holder or slide I is provided with massive rigid upper and lower. extensions H and I2 fitted to slide in guideways I 3 and I4 respectively in the machine frame, and in which they are non-rotatable. They may be, prevented from rotation in the guideways by various means well known in the art, as by giving them a non-circular shape in cross section, providing splines and keyways, etc. A work spindle or shaft I5 is mounted rotatably in the holder H), with its 'axis transverse to the pathof movement of the holder and to the axis of the cutter, and carries on one end a chuck IS in which the work piece is mounted. The other end of this shaft carries a mastergear H which constitutes one element of means for correlating the rotation of the work piece with the rotation of. the, cutter. The cooperating parts for this purpose comprise a pinion l8, meshing with the master gear and carried by a shaft l9, a worm wheel Zll-fixed to shaft IS, a worm 2! meshing with worm wheel 20, and a train of gearing between the worm 2| and a worm 22 which drives a Worm gear 23 through which the cutter-spindle 24 is adopted to slide endwise and with which it has a rotation transmitting connection. By way of illustration, a motor 25 is shown here as mounted in the base-of the machine, driving a shaft 26 through reduction gearing, and shaft 26 drives a transverse shaft 2'! which drives the worms 2| and 22 through bevel gear pairs 28 and 29, respectively.

The movement of the'work holder H1 is controlled by a cam 30 against which a follower roll 3| mounted on the lower extension l2 of the slide bears; andis held by gravity. The cam is rotated at a speed proportional to that of the master gear I! by worm and wheel gearing 32, 33 and transmissiongearing from the shaft 26 substantially as shown. In this illustration, the opcrating surface of cam 30 extends through less than 360, while the spiral of the face gear teeth extends through considerably more than 360.

The outline and speed ratio of the cam are established pursuant to known principles of machine design so that the work holder and work will descend or rise, as the case may be, at a rate in proportion to the rotation of the work such that -motor if desired.

each .point in the spiral line of teeth, when it arrives beside the cutter, will be between the limits of reciprocation of the cutter.

With the arrangement shown, the work holder is at its highest point at the commencement of the cutting operation, and the operation is begun at the'innermost end of the spiral; the holder being then graduallylowered as the cutting proceeds. But either of these conditions may be reversed. That is, the cutting action may be commenced at the outer end of the spiral, and the holder may be raised with progress of the cutting from that end. It is obviousalso that other cams may be substituted, including those having a spiral surface or groove extending throughout an entire convolution or a number of convolutions.

.When teeth are cutin a closed non-circular circuit, a cam is employed which causes both rise and descent (or vice versa) of the work holder in the course of the cycle.

Other parts of the machine shown are in substance like corresponding parts of the standard Fellows gear shaping machine. Thus the cutter spindle 24 is reciprocated by a gear segment 34 meshing with encircling rack teeth 35 on the spindle and .reciprocated by a connecting rod 36 from acrank on a shaft 31 driven by the motor 25. through gearing (not shown) or a separate In so reciprocating, a guide element carried by the spindle slides in contact with a complemental guide element in the hub of worm wheel 23.

machine is set up to generate face gear teeth conjugate to spur gears; and helical guide elements are used in generating face gears conjugate to helical pinions. Guides of these characters are shown and described in the Fellows Patent No. 676,227, June 11, 1901.

The cutter is backed off from the work to avoid rubbing during its non cuttin strokes, and is held in a fixed path while making its cutting strokes. 'I'o permit of such movements a saddle 38,.which contains the spindle 24 and worm wheel 23, is pivoted to swing through a small angle around the axis of worm 22, and it is forced away from the workiby a spring (not shown) and to- .ward the work by a cam 39 on shaft 31 acting through a lever 40 and transmission rod 41.

Saddle 38 and the shafts 31 and 21 are supported by acarriage 42 which has sliding movement on thebase toward and away from the work holder ID for feeding the cutter to depth in the work (when the character of the work requires such a feed) and for withdrawing the cutter to provide space forchanging the work. Such movements are given to the carriage by means of a depth feed cam 43'and spring 44 acting through a gear segment 45 and a rack element 46 on the carriage. This vdepth feeding mechanism is in principle like that of the Fellows Patent No. 1,478,472, December25, 1923, and the feed cam may be driven from the motor 25 or shaft 26 by any appropriate mechanism. Preferably the teeth of rack 46 collectively form a helical thread surrounding a rotatable bar 41 mounted in the carriage, which bar can be rotated to alter the position of the 7 These guide elements are parallel with the axis of the spindle when the carriagexin; accordance with Clittfiflit andiwork pieces of difierentzdimensionss To maintain rdrivinaiconnection between shafts? 25 and i 2 1?in::di*fferent: positions of the carriage; the. shaita 26 is coupled by a telescopic shaftisectiona 48 andiuniversaljoints with a vshaft sectionxtfl' mounted the"; carriage and :cormectedrby; gearing 50 with shaft 21. Shaft 21 is insplinedslidina connection with: the driving member ofthe geanpairi 28; and

advancing end o-f :the'latter; But in cases where the Work gearteeth form aclosed-circuit or wherevthe tooth spaces are i out within the-a surfacezoi-tthe face gear blank; aedepithi :feed is neces+ sary..

Various modifications from thetmachine organization here; shown may be made within :the scopenof the; invention; These drawings arernot intended to show thestructural details of a com-P pletet commercial machine, butsrather to-explain thewprinciples of the invention-in: terms suhiciently full toena'ole draftsmen fam'iliar with this :art to embody such principles in oo-miner- Foriinstance when' teeth are out ;in

shaft 21 toiworint pore to worm 22;;according to? known principles. Provisions; are made: for substitutingdifferent master-gears antlehinions forrj oneranother; the. master. gear being klocated and LSECHI'fid'. on the-shaft by a dowel 5 and t a removable screw 52; the pinionx i8being ma/de cially practical form. Hencethedrawings are largely diagrammatic and 'manyv parts areomit ted which Would: beneeded in a commercial ma chine. but illustration of which is not necessary for the information of the skilled workercin the art o f building an operative machine; t l

oppositeends-ofia work spindle or shaft" i5 rotat ing iria. work holden Hli which reciprocates'in It will bereadilyapparent from the present illustration that, with the cutter, workand work holder in the position shown in Fig. 3, reciprocation of the cutter causesthelatterto move across a zoneoi the work piece W near the axis thereof; A. rib Trprojectingirom suchzone across the nearer sideof the cutter path is intersected and cut-by the cutter. Shaft 27, through the worm and-wheel gearings 22-43 and 21-28, rotates the cutter andfthepinion teat harmonious speeds; Thesespeeds may be. identical, and they are-identical when a pinion ii? of the same diameter and having the same number of teeth as the-cutter-is usedi Said pinion rotates the work spindle fishy-its coaction with the master gear 17, andtherehya rotates! the gear blank W at the'same angular speed." Such simultaneous rotation of the cutter andwork, occurring while the cutter is rapidly reciprocatingcauses the cutter to generate and cut teeth in the protruding: rib r conjugateto the tooth outlines -at the cutting edgesof the cutter, and to all other gears having teeth ofzthe same pitch and pressure angle. The spacing of the teeth out in the work piece ismthesame asthatof the master 'gearqteeth.

Teethofl-augiven pitchlma-y beqcut with the i AZ-23 is establishedin correct proportion. Con-' versely, Work'gear teeth with different pitch spacimgrfrom; that of the master gear I! may be out hyv suitably speeding: the mastergear I! and pinclle l5; Change gearsof suitablevalues for such purpose may be interposed in thedrivefrom dependently rotated master gear. ll.

accessibleefor: removal and?" substitution of: other pinionsby removal of A ahea'ring 53 in which the lower endof shaft l9 is heldrfor operation.v

As i the: Work 1 rotates; the: work holder; 18w is progressively loweredby; gravity under control of the can; 30 :which; as-previously stated; is ro tated at; a fixed; speed ratio to the: rotation: of the cutter: and a correlatedspeedqratio1to the master gearing-,1 and; has a surface shaped .to

maintainwthe teeth of. themaster gear" always atithe same height asttheyz pass through the pitch pointiwith'thewmasterpinion; The master gear H and workpiece rotate at constantly changing angular velocities when the" master pinion i8 is turnedat uniform angular velocity because the distance of the pitchpointfromithe center of the master gear is contimtously chang ing; Thisfactor-ris taken: into account tinidee signing the-form of; the-10am.

Another emhodimentiof the invention is 'ashown in Fi-gs. 5andz6f Thisin': principle is substantially likethat first described: but difiers principally 'iri' the mannerwhereby the rotation 'of thewmaster geargwork piece; andcutter areicontrolled Instead of drivinghthe master gear'and work" piece bymeans of a master piniontjthe mastergear is independently driven and controls therotation'ot the masterrpinion and cutter; In:this: case; as in the previous one,:1the'work piece W 'andnmaster gear I l are mounted zon' .the

guides :l3 rand M; having-extensions llandsiz fitting the guides, and is'suppiorted by a camfifi througlra camiollower 'rolt 3| connected to the extensionilzo-fthework carrier. But theshaft shaft-5.7; Aashaftc. 58 isalinedwithshaft 53 andcou'pled thereto by a: sliding splined'couplirrg 59 to allow for rise and desc'ent of the work holder; Shaft 58-1carriesfa;v wormditt which meshes withva wnrm wheel 6 secured to shaft l5. and isv heldini continuous mesh with the worm wheel during up and down movement'hof the-"holders ID; by bearings .on said" holder; Shaft 51 rotates cam iificthrouglr a WOImfiEiIOn the shaft, a worm wheel E4201! shaft 65, change gears 66, Bland shaft fifion which both the cam and the gear 61 are secured. l

Torquetending. to rotatevthe master pinion-18 and cutter C is applied bya torque motonfiil through a pinion lll and facevgear ll to a-i-shaft 12 on which worms Hand 74' are secured mesh respectively with worm wheel Zil on thepinion shaft l9 and worm wheel 23on the icutterspindle 245" The pinion l8, althoughhrivehby the' motor 69, turns only as fast as is permitted byvtheim This 31':- rangementibetter' controls a the rotation of" the pinion and. cutter, as thetorquein the'shaft I9 is constant. There is no'backlash in thewrotation of thepinions The cutter of :course rotates at therate established by the "fiWQWROI'l'I'li and wheel gear pairs LL-2i! and T t n-'23.. Ordinarily its rate'of rotation is equal to that Qfilllle master pinion, but this is not an essential condition, v

The cutter is reciprocated and backed off, for relief on noncutting strokes, by a motor I acting through means substantially like those shown in Miller Patent 2,107,543, February 8, 1938, and in principle the same as the corresponding means shown in Fig. 3.

The variable speed transmission drive 56 is provided tomake the number of strokes of the cutter per revolution uniform at all times, or as nearly so as feasible. Assuming that the motor I5 runs at constant speed, then if the master gear were also rotated at constant angular velocity, the cutter would make fewer strokes per rotation while cutting the outer parts of a spiral line of teeth than when cutting the parts nearer the axis.

Therefore the transmission drive is constructed and operated to rotate the workand master gear at slower angular velocities when teeth of the master gear more remote, from the axis are in mesh with the pinion I8 than when teeth nearer the axis are in mesh with the pinion. The transmission here shown is of the V belt and pulley type having a belt 16 of V section passing around a pulley I'I, composed of separable cones splined to the shaft 51, and a similar pulley I3 splined through a cam follower 89 and connecting rod 90.

This is one of a number of different means which may be used for the same purpose within the scope of the invention. Conversely, a like or equivalent variable speed transmission may be interposed between the motor 15 and the mechanism which reciprocates the cutter and may be timed with the travel of the work holder to reduce or increase the rate ofreciprocation of the cutter spindle. Or the speed of either the motor 55 or motor "I5, or both, may be appropriately varied during the travel of the work holder to the same end. Such motors may be electric or hydraulic or of any other suitable character, all within the scope of the invention.

A third form of the invention is illustrated in Figs. 7 and 8. Here the'master gear is omitted and the linear rotational speed of the cutter is equalized with that of the work piece at different distances from its axis by other means timed with the travel of the work holder.

The cutter spindle is reciprocated and backed off by a motor 75 acting through means substantially like those shown in Fig. 5, all mounted in a carriage 42 which is supported slidingly on the machine base and is associated with depth feed means substantially like that shown in Fig. 3 and previously described, but arranged to operate in the opposite direction.

The work spindle I5, like those of the previous embodiments, is supported in a slide I0 which is reciprocable vertically in guideways (not here shown) and is raised or lowered by a cam 30 of the same nature asthose previously described.

The work spindle and cam are driven simultaneously at the prescribed speed ratio by a shaft 9| which, in turn, is driven by a prime mover. For the present explanation, it may be assumed that such prime mover is an electric or other motor (not shown) mounted conveniently in or on the machine base, geared to the shaft Si by a belt and pulley drive 92, 93, a worm 94 connected to the pulley, and a worm gear 95 secured to the shaft 9| and meshing with said worm. Shaft 9| is connectedthrough a splined sliding coupling 99 with a worm 91 which meshes with a worm gear 98 on work spindle I5. Shaft 9| carries a pinion 99 in mesh with a face gear I00 on a shaft IOI which, through change gears I02 and I03, drives a shaft I04 and a worm I05 on said shaft meshing with a worm gear I06 secured t the cam shaft I01. r

The cutter is rotated by a torque motor I08 through shaft I09, telescopic shaft section IIO, universal joints III and H2, shaft section II3 supported in carriage 42, bevel gear pair I I4, shaft '5, bevel gears H6 and H1, worm H8, and worm gear I I9; the latter surrounding the cutter spindle 24 and being engaged therewith by rotationtransmitting guides of the type previously described. The speed of such rotation is restrained and correlated with that of the work by the following mechanism.

Shaft i09 carries a pinion I29 which, through face gear I2l, shaft I22, change gears I23, I24,

worm I25 and worm gear I26, tends to rotate a screw I21, confined against endwise movement, but rotatable, in a bearing, I28. A slide I29 is engaged with a guide I30 so as to be movable in alinement'with screw I27 and is provided with an internally threaded portion I3I with which the screw I2! meshes. Thus the cutter spindle can rotate only when the screw I2! is permitted to rotate by displacement of slide I29, and its speed of rotation is governed by the speed of displacement of the slide. 7

Such displacement is caused, or permitted, to occur in the direction in which screw I21 tends to displace the slide, by the work-spindle rotating means, at a varying rate timed with the rotation of the work spindle. The slide I29 is formed with a transverse guideway I32 in which is fitted slidingly a block I33 connected by a pivot I34 with an arm I35 secured to a shaft I36, to which rotation is imparted from worm shaft I04 by ratio gears I37 and I38, a worm I39 and a worm gear I40 secured to the shaft I35. In short, there is a positive train of gearing between shaft 9I and shaft I36, which causes arm I35 to revolve at a definite predetermined ratio to the rotation of the work. As the arm swings from a position in which it is, say, parallel to the path of slide I29 (the position shown infull lines in Fig. 8), to a position at right angles to said path (shown by broken lines in Fig. 8), it allows the slide to advance at an increasing rate of speed. When the guideway I32 is straight and perpendicular to said path, as shown in Fig. 8, the speed range is from zero to the full linear speed of pivot I34,

and the rate of increase is proportional to the versed sine of the increasing angle which the arm makes with said path. Then, assuming that the action is started with the work spindle axis at the height of the cutter, that the work holder descends from this position, and that the arm I35 'modified conformably with the required speed ratios; or a cam of appropriate contours is subspindle.

agevmoc effecting a relative displacement between the workspindle and cutter spindle such as t'obring portions of the workpiece at different distances from-the work spindle axis within the range of action-of the cutter. They include means for simultaneously rotating the cutter and work spindles and means for varying the angular velocity of one spindle relatively to'the other concurre-ntly with suchrelative displacement, insuch manner as to effect equality,- or such other ratio as may be desired, of linearpitch line velocity of the'cutter-with the linear velocity of that part of the-workpiecewhich is nearest to the cutter. The means forthe latter purpose ofithe first and second forms hereindescribed arealike in that they include a master gear and transmission connections between the master gear and work The second an third forms arealike in that the work spindle and cutter spindle are rotated bydifierent agencies and the'ro'tational speed or thecutter spindle is variedby means timed with the relative displacement between the workspin'dle and' the cutter. In these two last-- mentioned "forms the master gear and theslide such as that shown in :Patent *No; 2,304,586, granted 'De'cemhen' 8, 1-942; on' -the-= application of Edward-WE Miller Serial No. 3? 0,21'2ffild Decemlot-r 14, '1940,may be used. "Such a hob, when employs d-for' the purpose; is mountedon a spindle whiclrektends transversely'to the path or relative displacement between "the work spindle and cutter; instead or parallel tosue'h path, but its speed of I rotation,- or that off the work spindle, is conlled by means substantially *like those herein described to I harmonize the displacement of the hob teeth due to theirhelical" arrangement with the linearvelocity or portionsof the work piece at' different distances"'from= the *axisthereof.

What we cIaim'a'n'dj desire'tosecure by Letters Patent-is:

"1. A machine for "generating face gears with teeth located at relatively 'difierent distances iro'm its axis, comprising a work holder, a work:

spindle mounted rotataloly' 'in said holder *and havingmeans for securing a face gearblank with its *face substantially perpendicular to "the rotational axis of the spindle 'a cutter spindle-and a tooth-"generating cutter *secured thereto mounted rotatably with the cutter ii -position 't'o incise a gear blank secured to the work spindie, "means f or imparting'cut-ting and generative verse tothe axis ofthe workspindieand cit-tend- ]19 are generically equivalent in being devicesfor restraining therotation of thecutter spindle and oausin'g'itsspeed to be varied proportionallyto the varying distances from the workspindlebi different'parts of the work piece'on which the cutter acts. 7

The invention, however, is not limitedtoth-e forms and designs "of machines hereillustratcd, for many variations may 'be madei'n the'construction and arrangement of the parts, and equivalent means may be substituted-for imparting."mo-tion to themovable parts. "For ins'tance, by suitable "reversals, the movement of *relative displacement for cutting parts ofthework at different distances from its center may be given'to the cutter supporting and -carrying means (and likewise to "the speed correlating means where mastergearing is used) instead of to the work holder. And, as previously noted, by arranging the work spindle axis parallel to the cutter axis or vice versa)' a and approximately varying the distance between the spindle axis and cutter,

gears of cylindrical type may be generated with teeth in spiral, or other non-circular arrange-l By gear of cylindrical type in this-(lea scriptionwe mean gears of which theteeth are merit.-

loc'ated on'the periphery of a disk, or plate, oron the i'nt'erior of aring; as distinguished from face gears.

of a reciprocablespindle as themeans'for giving the cutter its cutting'movements;since, for cutting some gears in which the lines of 'teeth'are ing in the general direction of the cutting comtion,-:a -work spindl'e holder supported and guided gear blank with one face thereof substantially r pe'rpendi'cular to the axis of thework spindle and to move i'n a path substantially-paraliel to the cutter-spindle, a work-spindle mounted rotatabliy in saidhoider with its'axis transverse to said: path and'having means-for securing a face M its prescribed path, and means for rotating the not too close together, or donotextendtoo'near] to theaxis or the'work piece, a generating l'i'olocutter" and work spindles with a varying angular velocity ratio proportional to'the varying distances from the axis of the gear'blank of difierent points on the face ofthe gear blank which arelbrought betweenthe limits of reciprocation of tlie :cutter byvirtue of the cam controlled movement of said holder. 3.:A machinefor'gene'ratin'g aface gear with teeth *at different distances fromits'axisfcornprising a rotatable and endwise-reciprocable cutter 'spin'dle, agear shaped planing cutter secured to saitl spindle, means for reciprocating said spindle between prescribedilimits of motion, a work spindle-mountedrotatably on an axis transverse to the axis of the cutterfspindle an'jd havin'g means-for securing a face gearblank with a face,

thereof substantially perpendicular to the axis of the work spindle and in position to be incised by the cutter, the work spindle being displaceable in a path substantially parallel to the cutter spindle t bring points of the face gear at different distances from the axis thereof within the range of cutting traverse of said cutter, means for so displacing the work spindle, and means for rotating the cutter and Work spindles at varying speed ratios proportional to the varying distances from the axis of the work spindle of different points on the face gear blank which are so brought within the range of the cutter.

4. A machine for generating face gears of which, different teeth of the same gear are at different distances from the axis of the gear, comprising a linearly movable work holder, means for supporting a face gear blank on said Work holder rotatably with the face in which teeth are to be cut substantially perpendicular to the axis thereof, a cam engaged with said holder' and organized t control the movement thereof in its prescribed path, a' cutter arranged contiguous to the face of a gear blank mounted on said holder and constructed to generate face gear teeth when it and the work gear are rotated about their respective axes at harmonious speeds, means for driving said cam to cause displacement of the work holder whereby points of the work piece at different distances from the axis thereof are successively brought into cutting proximity to the cutter, and means for simultaneously rotating the cutter and work piece, and correlating their rotation in harmony with the varying distances from the gear blank axis of points on the gear blank face which are successively brought to the cutter.

5. A face gear generating machine comprising a supporting structure, a tooth generating cutter and means for imparting cutting and generating components of motion to it mounted on said,

supporting structure, a gear blank holder having means for supporting a face gear blank to rotate about an axis substantially perpendicular to.

its face, and with its face in a location to be acted on by said cutter, the holder being mounted movably on the supporting structure with provisions for displacement in a path which brings points on the gear blank face at different.

distances from the axis thereof intopropiniquity with the cutter, and correlated mechanisms for effecting such displacement of said holder and for simultaneously rotating the gear blank, said mechanisms including means by which the speeds of such displacement and rotation are so related as to cause a zone of the gear blank face, nonconcentric with the axis thereof, to be moved past and in cutting engagement with the cutter.

6. A face gear generating machine comprising a supporting structure, a tooth generating cutterand means for imparting cutting and generating components of motion to itmounted on said supporting structure, a gear blank holder having means for supporting a face gear blank to rotate about an axis substantially perpendicular to its face, and with its face in a location to be acted on by said cutter, the holder being mounted movably on the supporting structure in guided engagement therewith for displacement in a path which brings points on the gear blank face at different distances from the axis thereof into propinquity with the cutter, and correlated mechanisms for effecting such displacement of the holder and for simultaneouslyrotating the gear blank at relative rates of speed such as to cause a zone of the gear blank face, non-concentric with the 'axis thereof, to be moved past and in cutting engagement with the cutter, combined with means for correlating the generative component of motion of the cutter with the rotational velocity of the gear blank in proportion to the distances from the axisof the blank of the different points in the face thereof on which the cutter acts. H

'7. A machine for generating face gears with teeth in non-circular arrangement about the axis of the gear, comprising a work spindle having means for securing a face gear blank, a master face gear having teeth arranged similarly to the prescribed arrangement of teeth to be cut in the blank, a cutter having teeth with cutting edges in outlines conjugate to the prescribed forms of teeth to be cut in the gear blank mount ed in cutting proximity to the face of a gear blank secured to said spindle, means for imparting to said cutter and the teeth thereof cutting and generating components of movement with respect to such gear blank, a pinion meshing with the teeth of said master gear, transmission mechanism between said pinion and cutter organized to correlate the rotational speed of the pinion with the speed of the generative component' of motion of the cutter simultaneously with rotation of the work spindle and master gear, and means for effecting displacement of said spindle and master gear with respect to said pinion and cutter at a rate correlated with the rotational speed of the spindle such as to bring successive teeth of the master gear which are at different distances from the axis of the spindle into meshing relation with the pinion and to bring corresponding points of a gear blank secured to the spindle into cutting relation with the cutter.

8. A machine of the character described comprising an endwise reciprocable and rotatable cutter spindle, a gear shaped planing cutter secured to said spindle, a work spindlemounted with its axis transverse to that of the cutter spindle having means for supporting a face gear blank with the end face thereof in cutting proximity to said cutter, a master face gear secured to the work spindle and having teeth in a line non-concentric with the axis thereof, a pinion meshing with the teeth of said master gear, means for simultaneously rotating said pinion, master gear and work spindle, means for displacing the work spindle and master gear in a direction and at a rate of speed correlated with the rotational speed of the spindle and the disposition of the teeth of the master gear such as to maintain the mastergear teeth in mesh with the pinion, and connections between the pinion and cutter spindle organized to maintain a prescribed ratio of angular speeds between them.

9. A machine for generating spiral face gears comprising a work spindle holder mounted and guided for rectilinear movement, a work spindle rotatably mounted in said holder with its axis transverse to the path of movement thereof having means for securing a face gear blank, a master gear having a spiral line of teeth, a pinion meshing with said master gear, means for rotating the pinion and work spindle, a cam, engaged with the spindleholder for controlling the rectilinear movement thereof, and means for rotating the cam, said cam having a surface so related to the arrangement of the master gear teeth and to the speeds of rotation of the work spindle and cam as to bring successive teeth: of the rotating master gear into correctmesh with the pinion.

1*0; -A machine for -cutting#spiral face 1 gears comprising an endwise reciprocable and rotatable cutter spindle, a gear shaped planing cutter mounted on saidspindle, a work-spindle, a work spindleholder mounted movably in a path substantially parallelz tothe axis of said cutterspindle, a work spindle mounted rotatably in said holder with'its axis transverse -to-the path of movement thereof having-means for holding a face "gear blankwith an en'd face: thereof incutting proxi-mityto the cutter, a spiral. master 'gear secured to the i work spindle in coaxial alinement with the gear blank apinionmounted -rotatably ontan axis parallel to the cutter spindleaxisin meshwith theateeth of :the master geanpmeans for rotating said-pinion and cuttersspindle simultaneously about their: respective faxes at a predetermined speedratio, and meansifor. displacing the :workspindle holder in its path: at. a 'rate correlated with the rotational. speed of the work spindlesand :the radial distances of successive mastertgear teeth from the axisuof the spindle, SOLE/S110 maintain the master gear teeth in correct mesh with the pinion and bringta corree spending :spiral .zone of the work gear blank into cutting relation to theIcutter. a 'llunvmachine according to claim. 10, in which the 'meanslfor shifting 1' the work spindle holder comprises :a camflandLmeans for propellingrzthe cam; =..the surface ofathercam .beingca. spirahproportionalcto the spiral ,line oflthe master gear teeth and to thevelocityratioof the work spindle andcam.

'rl2..i A:ma=chine for :generating face gears of,

which the teethuare at varyingcdistancesi from the axis, comprising .a workspindle shaving srneans for :holding'a facelgeanblanha holderifor said work spindle-movable, 1111a,: path transverse to the axis of .the spindle,'a generating cutter located inipos-ition to cutthe face .ota gear blankzheld by saidzholding" means and. having-teeth arranged toctravel withta component-of movement icontiguous: to the face of the-geanblank and tangential to a rcircleconcentric with the axis of the blank, means for rotating thework spindl-e means for shifting the spindle :holder in its .rprescribed path: atairate correlated with the rate of spindle rotation: such that a, prescribed non-circularzonev of the workpiece is traversed past the cutter in cutting relation thereto, and means controlled to impart thereto the generative component of its'movement at a rate raster than that-,of the nearest adjacent 'pointtof said zone, and means in timed relation with the rotation of the work spindle for restraining the speed of said generative component to a predetermined ratio with respect to'the speed ,of 'the ,1 gear. blank.

14. A spiral face gear generatingxmachine.com-' prising awork spindle having means for holding-a tace gear blankga holder for said spindle movable in; a path transverse to the axis of thespindle za geargshaped cutter and a cutter spindleto which the :cutter is securedmountedfor en'dwise reciprocation' substantially parallel to therpath of :the work spindle; holder, and for rotation, in a location-near to the work spindle. such that thercutter is enabled to :cut toothspaces in the, end face of a gearblank secured'to the spindle, means-for reciprocating. said cutter spindle, means; forrrotating 'the work spindle, means forzsimultaneously, displacing the work spindle: holder in' its path: at arateecdrrelated with the rate of rotation ofathe work. spindle to .bring a prescribed nonecircular zone aoi ithe gear blank into progressive .cutting relation to: the cutter, driving: means coupledwith the cutter spindle for rotatingthe same and tendingitorcarry the cutter teeth in their generating component of movement faster than the contiguous part ofthe before named zone otthework piece 'andemeans forrestraining the cutter spindie rotationtto: a rate in harmony with the linear travelof said contiguousrpart, of said. zone;

1:15. :A gear generating machine as set 1 forth 1111 claim 1:4,. in which the means for restraining :the

cutter spindle rotation comprises a master gear secured to the Work spindle having teeth .arrangedin ai line similar to the before named zone, a pinion in mesh with said ;master .geanand transmission: gearingbetween said pinion.land;the cutterrspindle. a l

16. VA 'gearxgenerating machine as setforth in claim l Liin' whichzthe meansfor restrainingthe bythe spindle rotating means .for imparting to the cutter the enerative componentofitslcutting :action ata rate of speedinharmonywith the speed of traverse past [the cutter of that portion of thebefore: named zone which isnext adjacent to.the cutter. V i

21-3. A m-achi.ne for generating face gears ofwhich: the teeth are at varying distances iromtthe axis,. comprisingawork spindle: havingmeans for holding! a face gear'blank, aholder for. said work spindlemovable in a pathtransverse to the axis of the spindle, ageneratingwcutter;located in position to out :the face of a-gear lolanklh'eld .by saidtholdingmeans and'having teeth. arranged to travel with a, component of movement. contiguous to theface of the gear blankiand tangential to thereto, a driver: coupledcwith *thecntter :tending rotation of the cutter comprises a screw geared,

to rotate at a given ratio to the cutter spindle :ro-

tati'on, a. linearly movable slide with whiclrsaid screw is .in .screw :threaded engagement, andv means'forcausing displacement of said slide ata rate lproportionalto the-linear speed ofathe :portioniof the work gear blank nextadjacent to the cutter and ina directionto permit. rotationof-said,

speed. of the part of the workpiece nextadjacent i to the cutter with the speed of reciprocating movement c of the cutter .18. .A .machine for generating successiveateeth are located at diiierent distances from-the axis of the gear, comprising a rotatable and endwise reciprocable cutter spindle, a gear-' rotatablyxon said holder, the, holder being. guided to move in a ;path which changes the distance betweensthe axisiofthe gear blank and the limits oftm'ovementof the cutter a cam engagcdwith the holder and-organized "to control the progress thereotintits prescribed-path, means .ior driving said cam :for causing displacement of the work holder whereby pointslofi the. gear: blanklat diffierent :d'istances lfIDlIl the :aXis i thereof are .succefs sively sbrought intoicuttingi proximity: to the;cnt-

gears of which ter, and meansfor simultaneously rotating the cutter and gear blank, and correlating their respective rates of rotation in harmony with the varying distances from the gear blank axis of the portions of the blank which are successively brought to the cutter.

19. A machine for generating gears with teeth in non-circular arrangement around the axis of the gear, comprising a work spindle having'means for mounting a gear blank, a master gear having teeth arranged similarly to the prescribed arrangement of teeth to be cut in the blank secured to the, spindle, a cutter having teeth with cutting edges in outlines conjugate to the prescribed forms of the teeth to be cut mounted in cutting proximity to the tooth-bearing portion of a gear blank secured to the spindle, means for imparting to said cutter and the teeth thereof cutting and generating components of movement with respect to such gear blank, a pinion meshing with said master gear, transmission mechanism between the pinion and cutter organized to correlate the rotational speed of the pinion with the speed of the generative component of motion of the cutter simultaneously with the rotation of the work spindle and master gear, and means for effecting displacement of the spindle and master gearwith respect to the pinion and cutter at a rate correlated with the rotational speed of the spindle such as to bring successive teeth of the master gear which are at different distances from the axis of the spindle into meshing relation with gear mounted on the work spindle having teeth 7 in a line non-concentric with theaxis thereof, an endwise reciprocable cutter spindle rotatable about its own axis, a gear shaped planing cutter secured to said cutter spindle, a pinion meshing with the teeth of said master ear, means for simultaneously rotating said pinion, master gear and work spindle, connections between the pinion and cutter spindleorganized to maintain a pre-- scribed ratio of angular speeds between them, a cam engaged with the spindle holder for controlling the linear movement thereof, and means for rotating the cam; the surface of the cam being so related to the arrangement of the master gear teeth and to the speeds of rotation of the work spindle and cam as to bring successive teeth of the rotating master gear into correct mesh with the pinion and corresponding parts of the gear blank into cutting mesh relation with the cutter.

21; A machine of the character described, comprising an endwise reciprocable and rotatable cutter spindle, a gear shaped planing cutter secured to said spindle, a holder for aface gear blank and a master face gear mounted for linear movement in a path substantially parallel to the axis of the cutter spindle and having means for rotatably supporting a face gear blank to rotate in a plane substantially parallel to said axis in cutting proximity to said cutter, a master face gear mounted rotatably on said holder, driving mechanism constructed and arranged to rotate said blank and gear simultaneously, a pinion meshing withsaid master gear, driving means associated with said holder for displacing the latter in its prescribed path so that the centers of the face gear blank and master gear are placed at varying distances from said pinion and the cutter, respectively, and means controlled by said pinion in its rotation for rotating the cutter at rates in harmony with the linear speed of points on the face gear blank variously distant from the axis thereof.

22. A machine of the character described, comprising an endwise reciprocable and rotatable cutter spindle, a gear shaped planing cutter secured to said spindle, a holder for a face gear blank and a master face gear mounted for linear movement in a path substantially parallel to the axis ofthe cutter spindle and having means for rotatably supporting a face gear blank. to rotate in a plane substantially parallel to said axis in cutting proximity to said cutter, a master face gear mounted rotatablyon said holder, driving mechanism constructed and arranged to rotate said blank and gear simultaneously, a pinion meshing with saidmaster-gear, driving means associated with said holder for displacing the latter in its prescribed path so that the centers of the face gear blank and master gear are placed at varying distances from said pinion and cutter, respectively, means controlled by said pinion in its rotation for rotating the cutter at rates in harmony with the linear speed of points on the face gear blank variously distant from theaxis'thereof, and.

40 means both mounted on said supporting structure, a cutter spindle mounted to rotate and reciprocate endwise on said cutter spindle holding means, a cutter carried by said spindle and provided with peripheral teeth adapted to perform a cutting action when the cutter is moved lengthwise of the spindle axis in engagement with a work piece, means for reciprocating the cutter spindle and cutter in a path of limited length, a

work spindle mounted rotatably on said work spindle holding means with its axis transverse to the cutter spindle, located and having means for carrying a face gear blank in operative relation to the cutter, one of said holding means being movable transversely in the direction of the.

cutter reciprocation so as to alter the distance between the 'axis of the work spindle and the limits of movement of the cutter, and driving mechanism including machine elements organized to rotate the cutter, other machine elements organized to rotate the work -spindle,other machine elements organized to cause displacement of said translatively movable holding means, and correlating means for controlling the relative speeds of said machine elements whereby to cause a noncircular zone of the work piece to pass the cutter and teeth to be generated in such zone.

24. In a face gear generating machine having a supporting structure, a cutter spindle mounted on said supporting structure to rotate about its axis, a cutter secured to said spindle having peripheral teeth and means for imparting movements to said spindle such as to cause the cutter teeth to have generative and cutting components of movement in action on a work piece presented in operative relation to said teeth; a work spindle.

holder, a work spindle rotatably carried by said holder and having provisions for securing a face gear blank with the face thereof in which teeth are to be generated substantially perpendicular to the axis of rotation of the work spindle, said holder being mounted on the supporting structure and guided to move in a path transverse to the axis of the work spindle in a location such that points on the face of such a gear blank at different distances from the axis of the work spindle are brought into operative propmquity with the cutter in consequence of movements of the holder, mechanism organized to cause the 1 holder to be displaced along its prescribed path of movement, mechanism for rotating the work spindle, and means for correlating the actions of said mechanisms so that a prescribedzone on the face of the gear blank which is otherwise than concentric with the axis of the work spindle is caused to travel past the cutter at a prescribed speed ratio with respect to the generative com 1 ponent of movement of the cutter.

EDWARD w. MILLER. ARTHUR I. BEAN. 

